Boeing developed a device for displaying positions of components at appropriate positions of an aircraft a on a head mounted display (HMD) when assembling the aircraft in the early 1990s, and the term “augmented reality (AR)” was derived for the first time in a paper that published this study. Research into the augmented reality has been started from this time. The augmented reality is currently being actively studied.
The AR is a technique for displaying a three-dimensional (3D) virtual object to be superimposed on a real world image (or real image) and improving the understanding of a real world by synthesizing a real world environment and a graphical virtual reality in real time based on reality. The purpose of the AR is to provide additional information or meaning about an object or a place actually observed. As compared with a virtual reality technique, the AR is reproduced by using a computer that can simulate various sensors, display devices (visual, auditory, tactile/tickling, or the like), and any phenomenon (fact or fiction) with interaction, and a virtual experience is created.
Techniques for 3D object tracking and scene restoration allow a user to register a 3D virtual object with some geometric transformation applied to a real space.
The augmented space increases virtual objects in a meaningful physical space authored by a service provider (for example, museums, tourism, model houses, interiors, games, and the like). Therefore, its physical objects may be generally pre-sampled and they can be tracked. This makes it possible for a user to interact more naturally and abundantly in a wider 3D space by various combinations of virtual and real situations. In this context, it has increased the importance of the partial 3D space centered at a particular moment by a head mounted display of a user in the field.
Considering a user in a wearable AR situation, it is difficult to directly apply egocentric metaphor and existing volumetric selection techniques to an augmented space in a virtual space. The biggest problem is physical boundary conditions from real objects. A user who meets obstacles so as to acquire an object of interest (OoI) at a certain place differs from a user in a virtual space with free transformation. For example, a target object is susceptible to damage by a user, may be disturbed by a surrounding environment, may be too small or too far away to be touched, or may be inappropriate from a combination thereof.
In order to solve these problems, far-sighted target selection or indirect pointing technique is an alternative to a viewing target.
However, the existing indirect approaches has a problem in that they cannot precisely select a 3D volume desired by a user, including IoOs and surroundings thereof.